Agung , Indonesia :

On the basis of the results of the visual and instrumental data analysis and considering the potential threats of danger, on November 27, 2017 at 06:00, the status of G. Agung returned from Level III (SIAGA) to Level IV (AWAS). Since yesterday and until today visually the volcano is clearly visible until the appearance of the mist. Crater smoke is fine, medium pressure, white, reaching a height of about 500 to 1000 m above the peak that disperses to the west and east. At night, a brief glow of the incandescent lava was seen in the crater. This day, there is no explosive eruption and no recorded tremor « off scale ».

The seismographs on December 04, 2017 recorded:
14 shallow volcanic earthquakes (VB)
4 deep volcanic earthquakes (VA)
No local earthquake.
No earthquakes of explosive eruption.
29 Low Frequency events.
No earthquake emission.
2 events of the harmonic Tremor type.
A continuous tremor with an amplitude of 1 to 2 mm and a dominant value at 1 mm.

As of 05 December 2017 (from 00:00 to 18:00), it has been registered:
No earthquake emission.
18 low Frequency earthquakes.
2 shallow volcanic earthquakes (VB)
3 deep volcanic earthquakes (VA)
No local earthquake.
A continuous tremor with an amplitude of 1 to 2 mm and a dominant value at 1 mm.

Recommendations:
Communities around G. Agung and climbers / visitors / travelers must not ride or do any activity in the Danger Zone around the crater of G. Agung and in all areas within a radius of 8 km around the crater of G. Agung. A sectoral extension has been added north-northeast and south-east-south-south-west up to 10 km from the crater of G. Agung. The estimated area risks are dynamic and continuously assessed and can be modified at any time based on the most recent observational data from G. Agung.

Flights began resuming when the airport reopened on Wednesday, after the wind changed and blew the ash away from flight paths. Individual airlines make their own decisions on whether to operate. Australia’s Jetstar resumed flights on Monday, while Virgin Australia Holdings Ltd said it planned to do so on Tuesday. Despite the resumption of some services, China’s aviation authority was stopping any more flights after the return on Monday of the last charter flight, bringing to 15,237 the number of stranded Chinese tourists brought home, the People’s Daily newspaper said on its Twitter page.

“China’s aviation authority has suspended all flights from Bali to Chinese cities until volcanic ash threat clears,” it said. China Eastern Airlines and China Southern Airlines, which stopped flying new tourists into Bali last week, told Reuters that any resumption of flights would depend on the situation. China Southern, which flies to Bali from the cities of Shenzhen and Guangzhou, said in an email that “due to volcanic activity in the area, the local airport and associated routes are not airworthy so flights on these two routes have been cancelled in the near term”. China has overtaken Australia this year as the biggest source of international visitors to Bali, representing about a quarter of the 4.9 million arrivals from January to September, according to industry statistics. Airlines avoid flying through volcanic ash as it can damage aircraft engines, clogging fuel and cooling systems, hampering pilot visibility and even causing engine failure. Purwo Nugroh, a spokesman for Indonesia’s disaster mitigation agency, said on Twitter that Mount Agung was no longer spewing ash but just white smoke that reached a height of 1,000 metres early on Monday.

Source : VSI , Magma. Reuters.com.Photo : REUTERS/Darren Whiteside

Sabancaya , Peru :

The average number of explosions decreased slightly during this week, averaging 69 explosions a day. The predominance of fluid movement-related earthquakes ( Long Period type) continues, followed by tremor activity associated with ash emission (2 hours per day). Events that indicate magma uplift (hybrid earthquakes) continue to occur sporadically and are of low energy. 
The eruptive columns of gas and ash remained similar to the previous week, reaching a maximum height of about 3300 m above the crater. The dispersion of these materials occurred within a radius of about 40 km, mainly to the southwest and northeast.


The volcanic gas (SO2) flux recorded on November 28 has a maximum value of 2036 tons / day, a value considered large. 
There were 8 thermal anomalies recorded according to the MIROVA system, with values ​​between 1 MW and 44 MW VRP (Irradiated Volcano Energy).
The eruptive activity remains constant. however, the frequency of explosions decreased compared to the previous week. No major changes are expected in eruptive activity for the next few days

Explosions sent ash up to 10 km a.s.l. on 04 December, 2017, ash plume is extending to the northeast from the volcano.

Volcanic Activity Summary:
Satellite data show an ash plume extended about 127 km to the east-north-east from the volcano.
Explosive-extrusive eruption of the volcano continues. Ash explosions up to 32,800-49,200 ft (10-15 km) a.s.l. could occur at any time. Ongoing activity could affect international and low-flying aircraft.

Turrialba , Poas , Costa Rica :

Turrialba Volcano: activity over the past 24 hours
The Turrialba volcano maintains a permanent degassing. The plume is less than 500 m above the top of the volcano.
Seismic activity was characterized by the recording of discontinuous volcanic tremor signals of low to moderate amplitude.
At the time of this report, winds at the top of the volcano are heading southwest.

Volcano Poás: activity in the last 24 hours
The Poas maintains a permanent degassing. The plume rises less than 500m above the bottom of the crater. No ash emission was detected.
The level of seismic activity is low.
At the time of this report, winds at the top of the volcano are heading southwest.